Single-Phase Pressure-Drop Measurements Over Low Void Reactivity Fuel

Abstract

An experiment has been performed to obtain pressure-drop measurements over Low Void Reactivity Fuel (LVRF) bundles in Refrigerant-134a flow. Production LVRF bundles were inserted into the test station with either an uncrept or a 5.1% crept flow channel. For comparison purposes, several production Bruce 37-element bundles were also included in the test string. Overall, the single-phase pressure drop of the LVRF bundle is slightly higher than that of the Bruce 37-element bundle. Pressure-drop measurements were used to derive bundle and junction loss coefficients for hydraulic calculations in safety analyses. Applying these loss coefficients, an assessment showed that the overall pressure drop over a string of 12 LVRF bundles (after core conversion) remains less than that over a string of 13 Bruce 37-element fuel bundles (before core conversion) at the Bruce Nuclear Generating Station.